Sail E0 Webinar
Question
If z1,z2 and z3 are complex numbers such that
|z1|=|z2|=|z3|=1z1+1z2+1z3=1,
then |z1+z2+z3|
Options:
A .  Equal to 1
B .  Less than 1
C .  Greater than 3
D .  Equal to 3
Answer: Option A
:
A
1=1z1+1z2+1z3=z1¯z1z1+z2¯z2z2+z3¯z3z3
(hence, |z1|2=1=z1¯¯¯¯¯z1, etc)
|z1+z2+z3|=|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯z1+z2+z3|= |z1+z2+z3|
(hence,|¯¯¯¯¯z1|=|z1|)

Was this answer helpful ?
Next Question

Submit Solution

Your email address will not be published. Required fields are marked *

Latest Videos

Latest Test Papers